Removable blade construction



Jan. 14, 1969A R. l.. swANKE ETAL 3,421,72

REMOVABLE BLADE CONSTRCTION Filed Dec. 1s. 1967 Sheet w m p n w. L

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`Han. 14, 1969 R. L. swANKE ETAL REMOVABLE BLADE CONSTRUCTION Filed Dec. 18, 1967 `Sheet United States Patent C) 3,421,742 REMOVABLE BLADE CONSTRUCTION Roy L. Swanke, Newington, and Gordon H. Raymond, Southington, Conn., assignors to Dynamics Corporation g; merica, New York, N.Y., a corporation of New or Continuation-n-part of application Ser. No. 637,703, May 11, 1967. This application Dec. 18, 1967, Ser. No. 696,680 U.S. Cl. 259-108 7 Claims Int. Cl. B01f 7/16 ABSTRACT F THE DISCLOSURE A removable blade assembly for high speed mixing devices wherein a spring is recessed within the female coupling member of the blade assembly. The spring has sufficient compressive force to prevent the detached assembly from resting on the drive stud, but is compressed by the additional weight ofl the jar. The spring may be recessed so as to bear against a headed shaft which abuts the drive stud.

This application is a continuation-in-part of U.S. patent application Ser. No. 637,703, led May 11, 1967, now abandoned, entitled Removable Blade Construction.

This invention relates to improvements in removable blade assemblies for containers and other devices and is concerned more particularly with a. removable blade assembly especially adapted for use with the containers of electric motor driven blenders such as the Waring Blendor.

One such removable blade assembly is shown and described in U.S. Patent No. 3,319,938 and assigned to the assignee of the present application. Although, the invention disclosed herein is not limited to use with that specific assembly, it will be described in conjunction therewith.

Broadly speaking, the above-mentioned patent provides a removable blade assembly for an upright container which comprises a body member extending through the bottom of the container, a rotatable shaft `supported within the body member and terminating in a coupling means beyond the bottom of the container, resilient seal between the body member and the inner bottom of the container, and camming means Iremovably secured to the lower end of said body member for biasing said body member downwardly and compressing said resilient seal against the inner bottom of the container.

The present invention deals basically with safety features relative to such removable blades. More specifically, it provides spring biasing means having sufficient strengh to prevent the blade assembly from being placed on a drive shaft without being first inserted into the container. Ad-

ditionally, bearing surfaces are provlded so that there is no danger of chipping the glass container when the blade assembly is inserted and removed.

The manner in which the present invention accomplishes these objects will be clearly understood from the following description when taken in conjunction with the drawings wherein: v

FIG. l is an elevational sectional view through the removable blade assembly of the present invention and a fragmentary section of the bottom of the jar;

FIG. 2 is a bottom plan view of the locking mechanism shown in FIG. 1;

FIG. 3 is a perspective view of the particular lockingcamming device used with the -present invention;

Patented Jan. 14, 1969 FIG. 4 is a sectional view taken along the line 4-4 of FIG. 2; and

FIG. 5 i-s a sectional elevational view of a modification of the present invention.

Turning now more specifically to the drawings, a jar 11 is partially shown with the normal opening through the bottom thereof. A body member 15 is secured to a shaft 21 and abuts against a shoulder thereof. A circular flange 29 is integral with an annular device 25, which includes a bearing surface 27, and extends thereabout above the opening in the bottom of the jar 11. A resilient ring 30 may be secured with in the ange member by means such as a press-fit for purposes which will become apparent as the description preceeds.

The shaft 21 is rotatably mounted within the bearing surface 27 and terminates at the lower end thereof in a coupling 22 designed to lit about the driving section of the blender (not shown).

The upper end of the shaft 21 may be threaded as at 18 so as to receive a nut 11. A blade 13 fits atop body member 15 separated by a washer 19 with the nut screwed down so as to maintain the blade firmly in place and rotatable with the shaft 21.

The depending bottom of the piece 25 is externally threaded at 31 so as to receive a nut 35 thereabout. Nut 35 is adjusted so as to `receive a half-ring member 37 thereabove. As may be seen clearly in FIG. 3, the half-ring 37 is supported between the arms 39 and 41 of a U- shaped member 43. The U-shaped member has a depending shoulder 45 at the outer end thereof and the legs of the U-shaped member 43 terminates in camming surfaces 47 and 53. Additionally, a linger-like bearing surface 51 extends upwardly from the U-shaped device 43.

When the device is in use, the entire blade assembly i11- cluding the body member and the annular device 25 are loosely fitted through the opening in the base of the jar 11 with the resilient sealing member 30 resting on the inner side thereof. The half-ring 37 is rotated so as to be at an angle with the U-shaped member 43 and is slipped above nut 35 as is shown in FIG. l. Then, by means of finger pressure on the shoulder 45, the U-shaped member is rotated upwardly in the direction as first shown by the dotted lines and ultimately to the position as shown by the solid lines in FIG. l.

Movement of the U-shaped member upwardly serves two purposes. First, the bearing surface rides against the nut 35, as shown in the dotted line, thus urging the halfring 37 tightly against the threaded portion 31. At the same time, camming surface 47 is bearing against the bottom of the glass jar and urging the entire lblade assembly downwardly so as to compress the circular seal against the inner bottom of the jar. When the mechanism has reached the point as shown in the solid line of FIG. 1. the blade assembly is rmly locked to the base of the jar and tightly sealed to prevent any leakage therethrough.

It will be noted that the cams 53 are provided on the opposite side of the U-shaped device opposed to the cams 47. Although it is preferable to use the locking mechanism as shown in the drawings, the lower camming surfaces 53 are provided so that should the U-shaped member be accidentally inverted, it will still provide the camming and locking action as required and described hereinabove.

It will now be obvious that it is a relatively simple matter to insert and remove the blade assembly of this invention. Therefore, the average user, such as the housewife, will have no trouble in removing the assembly, cleaning the jar entirely including the bottom thereof, and

the blade assembly and then reassembling the entire device.

AS stated above, relatively wide tolerances are allowed in manufacture of glass jars and there must be some means to accommodate for this. By camming the surface tightly and adjusting the nut 35 upwardly or downwardly, it is possible to get the exact camming action and resultant force desired for each jar. If desired, the nut can then ibe secured in that position during the original assembly at the factory so that it will not move and thus will always mate and match with the particular jar with which they are sold.

One problem arises with any removable blade assembly for use with a high speed blender. The blade assembly may be inadvertently placed on the mating coupling of the drive shaft without first being secured within the container. If the motor should be turned on under these circumstances, the very high speed may cause the assembly to fly off the drive shaft with sufficient force to become a dangerous missile. Even if the assembly remains on the shaft, it is possible that the exposed blade could cut someone severely.

In order to avoid such a possibility, a spring 26 may be secured in the female coupling of the assembly. One means for inserting the spring is shown in FIG. 4 wherein a borehole 24 is drilled in the upper inner section of the coupling and spring 26 is secured therein by any wellknown means such as by adhesive, spot welding or the like. Spring 26 extends downwardly into the drive recess area of the coupling 22. The spring is selected so as to have suflicient compressive force to support the weight of the blade assembly and insufficient compressive force to support the weight of the container. Therefore, the spring prevents the removable blade assembly from resting on the drive shaft unless it is assembled in the container. The container adds sufficient Weight to compress the spring and permit proper engagement of coupling 22 with the drive shaft. Accordingly, the desired safety feature has been provided without affecting the normal operation of the blender.

A further safety feature has also been provided by adding a metal sleeve 50 in the orifice at the bottom of the container. It will be noted that sleeve 50 has a ange which abuts the bottom wall of the container. This flange is of suliicient width so as to provide a bearing area for the cam surfaces 47 of the securing member. A seal 52 may be provided between the flange and the bottom wall of the container. The metal fiange prevents any possibility of chipping or breaking the container when inserting or removing the blade assembly.

FIG. shows a modification of the present invention. The arrangement of blade 63, body member 65 and nut 67 is substantially the same as shown in FIG. l. Bearing surface 77, ange 79 and seal 80 cooperate with the base of the jar 11 as discussed above, and the clamping assembly is the same basic mechanism.

However, in this modification, shaft 71 has a borehole 91 drilled axially therethrough. The borehole is reduced in size in the lower section 93 so as to provide a shoulder 92. A pin 94 having a head 95 is axially movable within the borehole so as to extend within the female coupling member 96. The pin head 95 abuts shoulder 92 so as to limit the axial movement of the pin into the coupling member to the position shown in FIG. 5.

Spring 97 is contained within borehole 91 as shown. When nut 67 is secured on shaft 71, spring 97 is compressed so as to bias pin 94 into the the position shown. Spring 97 has a compressive force sufiicient to support the weight of the blade assembly alone. Therefore, if the blade assembly is placed on the male coupling member, pin 94 will cause it to be ejected and fall to the side. However, when the blade assembly is properly installed in a jar, spring 97 has insuliicient compressive force to support the combined weight and pin 94 is driven upwardly into the borehole so as to allow a normal mating of the male and female coupling members.

It is to be understood that the above description and accompanying drawings are illustrative only and that the specific elements may be varied -without departing from the scope and intent of the invention.

We claim:

1. A removable blade assembly for an upright container which comprises,

a body member extending through an orifice in the bottom of said container,

a rotatable shaft supported within said body member and terminating in a female coupling means beneath the bottom of said container, said female coupling means adapted for mating with a male coupling means of a drive shaft,

spring means secured within said rotatable shaft and extending into said female coupling means, said spring having suliicient compressive force to support the weight of said removable blade assembly and insuicient compressive force to support the weight of said upright container,

a resilient seal between said body member and the inner bottom wall of said container, and

means for removably securing said blade assembly to said container.

2. The blade assembly of claim 1 wherein the means for removably securing said blade assembly comprises,

a U-shaped element terminating in camming means removably secured to the lower end of said body member for biasing said body member downwardly and compressing said resilient seal against the inner bottom wall of said container.

3. The blade assembly of claim 2 further comprising,

a metal sleeve extending through said orifice and having a flange abutting the outer bottom wall of said container, said camming means bearing against said flange.

4. A removable blade assembly for an upright container which comprises,

a body member extending through an orifice in the base of said container,

a rotatable shaft mounted within said body mem-ber,

a blade secured to the upper end of said shaft,

a female coupling member integral with the lower end of said shaft and 4adapted for mating with a male coupling on a drive shaft,

a spring secured within said shaft and extending into said female coupling member, said spring having a compressive force sufficient to support the -weight of said blade assembly and insufficient compressive force to support the weight of the container.

S. The blade assembly of claim 1 wherein said spring means comprises,

a pin member axially movable within said rotatable shaft and extending into said female coupling means, and

a spring within the upper portion of said rotating shaft tand exerting a compressive force biasing said pin member into said female coupling means.

6. A removable blade assembly for an upright container which comprises,

a body member extending through an orifice in the base of said container,

a rotatable shaft mounted within said body member,

a blade secured to the upper end of said shaft,

a female coupling member integral with the lower end of said shaft and adapted for mating with a male coupling of a drive shaft,

spring biased means secured within said shaft and extending into said female coupling member, said spring biased means having a compressive force sufficient to support the weight of said blade assembly and insufiicient compressive force to support the combined Weight of said blade assembly and said container.

. The blade assembly of claim 6 wherein said spring biased means comprises,

pin member axially movable within said rotatable shaft and extending into said female coupling member, 1

spring bearing against the end of said pin opposite said female coupling member and biasing said pin into said female coupling member,

and means for limiting the axial movement of said pin into said female coupling member.

References Cited UNITED STATES PATENTS Portmann 259-108 Berglind 259--107 X Kircher 259-107 Wayne 259-107 Stephens 259-107 X ROBERT W. JENKINS, Primary Examiner. 

